Whilst the existing agreement granted Eisai exclusive rights to market and distribute lorcaserin in 21 countries throughout US, the expanded agreement now includes most countries and territories worldwide, most notably, the member states of the European Union, Japan and China (but excludes South Korea, Taiwan, Australia, New Zealand and Israel).

Under this agreement, Eisai will be working in collaboration with Arena to develop and seek marketing authorisation of lorcaserin as an anti-obesity treatment in its territories. In addition to pursuing regulatory approval for weight management in the expanded territories, Eisai and Arena plan to investigate the potential of lorcaserin in new areas, such as: smoking cessation, a once-daily formulation, a fixed-dose combination with phentermine, as well as explore lorcaserin's impact on diabetes and cardiovascular outcomes.